Process for imparting flame retardant property to cellulosic containing materials

Abstract

A process for imparting flame retardant property to cellulosic containing materials comprising the steps; (1) treating the cellulosic containing material with a solution containing poly (hydroxy organo) phosphonium cation; (2) exposing the treated cellulosic material to an atmosphere containing ammonia to polymerize the phosphonium compound; (3) treating the cellulosic material containing the polymerized phosphonium compound with a solution containing a poly (hydroxy organo) phosphonium salt and a nitrogen containing compound copolymerizable with said phosphonium halide; and p1 (4) heat curing the phosphonium salt composition.

What is claimed is: 
     
       1. A process for imparting flame retardant property to cellulose containing textile materials comprising the steps: (1) treating the cellulosic containing material with a solution containing poly (hydroxyorgano) phosphonium cation;   (2) exposing the treated cellulosic material to an atmosphere containing ammonia to polymerize the phosphonium compound;   (3) treating the cellulosic material containing polymerized phosphonium compound with a solution containing a tetrakis (alpha-hydroxyorgano) phosphonium salt and a nitrogen containing compound copolymerizable with said phosphonium salt, and   (4) heating the thus treated cellulosic material to cure substantially all the phosphonium salt composition thereof.   
     
     
       2. The process of claim 1 wherein the phosphonium cation is present in the solution in an amount ranging from 10% to about 40% by weight; the phosphonium salt is present in an amount ranging from about 5% to about 20% by weight. 
     
     
       3. The process of claim 1 wherein the cellulosic material contains at least 20% by weight of a polyester material. 
     
     
       4. The process of claim 2 wherein the phosphorous compounds are tetrakis (hydroxymethyl) phosphonium cation for steps 1 and 3 respectively. 
     
     
       5. The process of claim 1 wherein the solutions in steps 1 and 3 are aqueous solutions. 
     
     
       6. The process of claim 1 wherein the phosphonium salt of Step 2 is cured by heating the treated material to a temperature between about 100° Centigrade to about 700° Centigrade. 
     
     
       7. The process of claim 1, wherein the phosphonium cation solution has a pH ranging from about 2 to about 9. 
     
     
       8. The process of claim 1 wherein the phosphonium salt solution of Step 2 is comprised of the following compositions:   ______________________________________                                    
                  parts by weight                                         
______________________________________                                    
phosphonium salt    10% to 40%                                            
a nitrogen containing compound                                            
copolymerizable with the                                                  
phosphonium salt    5% to 15%                                             
carbamic acid derivative                                                  
                    1%-10%                                                
water               remaining portion                                     
______________________________________                                    
     
     
     
       9. The process of claim 1 wherein the total resin add-on ranges from about 15 to about 35% by weight. 
     
     
       10. A composition of matter treated according to the process of claim 1. 
     
     
       11. A composition of matter treated according to the process of claim 4.